General library question

[eluser]xadio[/eluser]
I have been working on this so called "Advanced Loader", AL, however I am designing it for PHP4 so it can be used by all. I want to be able to dynamically make my factory products as well as fix the issues with CI's support for PHP5. Maybe I am going crazy or over the top, but I want this system to be as autonomous as possible. Right now it works in sync with CI_Loader as I want to allow the user to use either loader at the same time.

So far the AL will parse the requested library, using a preg_match and extracting extends and implements which it will then scour (customPath, currentPath, APPPATH.$this->libraryPath, and BASEPATH.'libraries/') for the requested classes and interfaces. It checks the Loader::_ci_classes / get_included_class() / get_included_files() to see if they have already been included else includes them. There are some things I still need to work out, but if you have some ideas please feel free to post. (ie I forgot about abstract class and need to readjust my regular expression to handle it.)

I can post the current development, but I am still working out some issues (ie eliminate infinite loops by recognizing this)

Code:

class Class1 extends Class2 {}
class Class2 extends Class1 {}

Some issues:
1) How to handle including a file with AL then needing it initialized with CI_L?
2) Which directories to search? How to handle each user's unique organizational patterns?
3) Should this completely take over CI_Loader?
4) Should this have another option of parsing a XML, configs, or (C, C++, Java) include style instead of parsing the class line?